[llvm] [SelectionDAG][RISCV] (add (vscale * C0), (vscale * C1)) to (vscale * (C0 + C1)) in getNode. (PR #144565)

[Philip Reames via llvm-commits]

https://github.com/preames commented:

This is a pretty big win, I'm a bit surprised we never caught this before...

https://github.com/llvm/llvm-project/pull/144565